1. Field of the Invention
The invention relates to powder pick-up tubes for use in delivering finely divided particles entrained in a suitable gas from a bulk container to a point of use. Although the invention is capable of delivering powder over a wide range of particle sizes, it is particularly useful with very finely divided particles that are normally extremely difficult to feed uniformly because of their tendency to agglomerate due to moisture pick-up and also electrostatic and van der Wal forces.
2. Description of the Prior Art
Devices of somewhat similar structure have been used in hydraulic excavation of river bottoms, although the purpose and structure of these devices was merely to raise gravel or ore deposits to an accessable location without regard to uniform delivery rate and without dealing with the problems characteristic of powder delivery systems.
Other powder delivery systems such as U.S. Pat. No. 3,472,201 to Quackenbush rely on the negative pressure within a hose to sweep in powder, but the present invention is believed to offer superior uniformity of delivery and better ability to break up agglomerations of the powder.